Software incorporated into a controller corresponding to production equipment has to be upgraded due to detected bugs or for improvement of functions and performance. Since such software for a controller corresponding to production equipment is installed by a maker of the controller before shipment, the upgrade has to be performed typically by the maker, a dealer company or the like.
Since manpower and cost for operation are required for every upgrade, it is known that the upgrade of a plurality of controllers corresponding to production equipment is performed via a network (see PTL 1, for example). In the structure described in this PTL 1, however, a user judges whether upgrade is to be performed or not.
Meanwhile another proposed technique is to determine automatically the necessity for upgrade of software for equipment connected to a network by using version information (see PTL 2). In the structure described in this PTL 2, the determination criterion on the necessity for upgrade is based on whether the distributed software is the newest version or not.